ECG quantification of myocardial scar and risk stratification in MADIT-II.

Published

Journal Article

BACKGROUND: Low left ventricular ejection fraction (LVEF) increases risk for both sudden cardiac death (SCD) and for heart failure (HF) death; however, implantable cardioverter-defibrillators (ICDs) reduce the incidence of SCD, not HF death. Distinguishing individuals at risk for HF death (non-SCD) versus SCD could improve ICD patient selection. OBJECTIVE: This study evaluated whether electrocardiogram (ECG) quantification of myocardial infarction (MI) could discriminate risk for SCD versus non-SCD. METHODS: Selvester QRS scoring was performed on 995 MADIT-II trial subjects' ECGs to quantify MI size. MIs were categorized as small (0-3 QRS points), medium (4-7) or large (≥ 8). Mortality, SCD and non-SCD rates in the conventional medical therapy (CMT) arm and mortality and ventricular tachycardia/fibrillation (VT/VF) rates in the ICD arm were analyzed by QRS score group. Both arms were analyzed to determine ICD efficacy by QRS score group. RESULTS: In the CMT arm, mortality, SCD and non-SCD rates were similar across QRS score groups (P = 0.73, P = 0.92, and P = 0.77). The ICD arm showed similar rates of mortality (P = 0.17) and VT/VF (P = 0.24) across QRS score groups. ICD arm mortality was lower than CMT arm mortality across QRS score groups with greatest benefit in the large scar group. CONCLUSION: Recently, QRS score was shown to be predictive of VT/VF in the SCD-HeFT population consisting of both ischemic and nonischemic HF and having a maximum LVEF of 35% versus 30% for MADIT-II. Our study found that QRS score did not add prognostic value in the MADIT-II population exhibiting relatively more severe cardiac dysfunction.

Full Text

Duke Authors

Cited Authors

  • Loring, Z; Zareba, W; McNitt, S; Strauss, DG; Wagner, GS; Daubert, JP

Published Date

  • September 2013

Published In

Volume / Issue

  • 18 / 5

Start / End Page

  • 427 - 435

PubMed ID

  • 24047486

Pubmed Central ID

  • 24047486

Electronic International Standard Serial Number (EISSN)

  • 1542-474X

Digital Object Identifier (DOI)

  • 10.1111/anec.12065

Language

  • eng

Conference Location

  • United States